If someone does have problems with interference from these converters (or quite a lot of electronics) then the fix might be to put a ferrite bead on the output cable close to the device. Arbitrarily picked eBay example:
https://www.ebay.co.uk/itm/10-20Pcs-Clip-on-Ferrite-Bead-Choke-Coil-Clamp-Rfi-Emi-Cable-Clip-Noise-Fil-UKTC/332895172548?var=&amp;hash=item4d821937c4&amp;enc=AQADAAADAFjVrDbVsZ8oH%2F8PNHtt9VX4%2Fw7FZcmMuqsX8uaFEduViZQycFraZcN76hYOMV0FKBoPtXZxqBRjSkEkD6MUe9BfsUKY4Kbn5iLQg%2B3WHNgn3%2BxsxAeKbeuJwoqXoOIy%2Bpb8Ym1Ue6e7BGeALFDg5tYvq10UEucTJ1yfzjuRqAKpdfwMUkWfnd9ofOgOQk16Em%2Fp6Sh%2B1gsETbAAWTvqmhPazTGTXcLvdw%2BEkT599aT33E4WPHjIzl5TpTgGNXyieIjQwYOfOKYiwAxAnO2VOXmVGJpoRB1oTfsFI%2F8kkm3akHImc8ezezQa9ME9EBvbjP4hNRfL9GRYUg05gFh6sbGzdBCBJjWKFwPgTmlxH4xRRQ8KCB9Cs%2FURDcwBpxh4SrVGwLiBOrf4qzsJMFZ9p%2B84Skt0nbj4DpFBSv0aME0t7ng6Ofszc1FBdCLnbYnHTMuEWl5HXqrDmungy8BK2b7sPxLjHI26nEuebAtu8%2Fw6gKBEz1uA%2B%2F9g5Zfdvm6IE44SX8WvihNsjkHTQ4R7T%2BBnzlFUfU73d4DqmktaYRuxdNz0Fg%2Fog3mMyL%2FwHDs1FL7nAC2VSiz1b2zusGkqD76O6%2FEBIn4tijDpcgWjVHXqhHYlYYFpOhM1ASg0RO%2BM%2BXSQsPMup%2BAz5RNyoFVLLvVZv7QKBF91w08Y5qJgo%2BayF5N2FmQrqgct99OfFkgSuf1%2BfA4P5vdO2f04hBRxJIkLf%2BDdJ6UTRSox54Qtlvk3lKnkpZN9RP31e7eVvqoXlG%2FkNWmwCSvUBKspZndFLk1KxqghQ%2F%2FT6IPpZYQn0V2xSVnbU3NpbS4b0ggjW%2FZTYWPa7d7dY9WC5%2B0l1tAobIZOKpHk%2Bvneu%2FfBPh1eVFgjjTjnJ3nxj8CtqJn01f2navGmbpvlbFuoQI6wFUNje2%2BCRCBgFPCs5Iy8vJRf2TzLeNlnTaIR3My0rUc0IMpGlGtUummcWv0loaRBljt7Z1Wqu8rG7Rb2cdJCmHdPmrVzIfI3RP4D4rdrdxmIBRWbPw%3D%3D&amp;checksum=332895172548920a8db2711548ec9e7b5ea93bf44984
Umm, that's a URL? Sorry.
I didn't pick the first eBay listing because it showed the cable just running straight through the bead. From what I've been told that's close to useless, you need to wrap the cable round at least once and preferably a few times.
I suspect the difference between “good ones” and others will be whether they have a choke of this sort on the output fitted internally.

When's “now”? I.e., which edition is your house? 2013, 4.1.7:
https://www2.gov.scot/resource/buildingstandards/2013Domestic/chunks/ch05s02.html
“Whilst an accessible entrance to a house is commonly the front or main entrance, an alternate entrance may be designated as the accessible entrance where this provides a more convenient or practical route into the dwelling.”
2017 handbook says exactly the same thing.

I've been in this rented house for 30 months now having replaced all the old halogens and incandescents with LEDs in the first few months of being here. I don't think I've had any failures. The only “problem” I've had is that I replaced one of the halogen E14 (SES) spots in the kitchen when it blew in the first few weeks I was here with a LED one which was much too narrow beam. Shortly after, I replaced all the kitchen bulbs with wider angle LEDs which have been fine. Not given the lighting any thought since.

Exactly, BT do not offer a broadband service in the sense that Openreach only guarantee a copper pair for speech quality to a certain standard (SIN5xx for some xx I can't remember, 516?). If it happens to work for broadband as well that's a bonus. If it cuts off everything above 3 kHz that's not their problem. I think it's different with FTTC and, of course, with FTTP.

I'd be paying £35/month for ADSL rather than VDSL.
At the time I connected BT were in the process of upgrading the exchange here and were taking no broadband orders. In addition, there was a problem with the previous tenant stopping the line so I could take it over. A&A got that all sorted for me though I finished up with VDSL because there physically weren't any ADSL ports available. Since then I've had no problems other than once where my IP address got DoSed for some unknown reason. A&A sorted that quickly and gave me a new IP address in a different block so all happy.
A while ago I was on PlusNet (so, effectively, BT) and had a problem on my line which took ages to sort out with “if it turns out to be your modem or wiring we'll charge you XXX pounds” nonsense. Not doing that again.

Maybe only useful for a few but an option not many know about: I have a “wires-only” broadband service where the copper pair coming into the house has only broadband on it, no voice telephone service. There's a recorded announcement on the line saying is in use so BT engineers don't think it's unused and reuse it for somebody else. For my “landline” connection I then use a voice-over-ip (VoIP) service.
Per month it's £10 for the copper pair, £25 for the broadband service and £10 to upgrade it to VDSL/FTTC. The VoIP service I use (sipgate) is free though you, of course, have to pay for outgoing phone calls which are at reasonable rates but don't have the various cheap/free rates that BT has. You can make emergency calls on the number when you've registered your address with them. The downside is that phone calls go through the modem/router and either a telephone adapter box or a computer (which may be a smartphone) so you need power to do that.
The advantage for self builders is that it's easy to move your telephone number when you move to the house and for a transitional period when you might want to be answering the phone on site during the day and where ever you're staying in the evening that's easy, too.
More: https://edavies.me.uk/2018/08/telephones/

Yes, but another ISP can provide broadband (but not telephone service) via BT Wholesale. I would be very surprised if, for example, Andrews & Arnold (just a happy customer) can't provide at least a basic ADSL service.
I'm not completely convinced that Sam's site is fully up to date; it says my exchange doesn't have FTTC but I know it does ('cause I've got it, didn't particularly want it but it was expedient at the time I connected and it's nice to have).

I think you mean the exchange is still “bundled”. That means that any ISP has to go through BT's modems and backhaul (from the exchange to their own routers) at the exchange end but still other ISPs can be used. If the exchange is unbundled then a few other providers (e.g., TalkTalk) can put their equipment in the exchange and you can get a line from them instead of from BT, though BT Openreach still has responsibility for the copper pair from the exchange to your house.
E.g., the local exchange I'm on at the moment is not unbundled (LLU services: No) so there's just BT equipment in it but still I get my broadband via Andrews & Arnold.

😀 The “correct” (i.e, standard) capitalization is kWh. The last column in your table should be labelled “kW” (not “kW per hour”) as watts are already a rate (kWh/h = kW). More details.
More substantially:
I'm not sure if it's worthwhile but if you want to do more detailed modelling then, yes, the angle of the insolation to the window does make a difference. Of course the simplest reason is the effect of the apparent area of the window being reduced when the sun's off the normal to the glass (cos θ) which is already taken into account by PVGIS. I think it also takes into account the effect of reflection off the outer glass surface using Fresnel's equations. However, if you're being this careful you'll have double or triple glazing so this will have a larger effect. If you want to explore that a bit more I have a calculator which might help.

You could ask the owner if you could buy an option on the land. You give them x thousand pounds to have the right to buy it for y thousand pounds in the next z years. If you can get planning permission then you buy, if you can't then you've lost x and the cost of the planning application. If they're done nothing with the land for quite a while then presumably y could be quite small and z could be quite long. You'd probably want a clause that says they can't object to the planning application!

But the grid is moving in the direction of being fossil free (and has been for short intervals in Scotland recently) whereas if a new build got an oil or LPG boiler in 2026 it'd likely still be a fossil burner in 2036 or 2046.

Went up to the site on Monday to get some 25mm sheets of Celotex out of the container into the house and cut them up into strips to go in the I-beams forming the window reveals. Got two out of the container, couldn't hold them into wind as planned so held them flat across the wind as I walked to the house door. Just as I was stepping across the ring beam for the porch/greenhouse towards the front door a gust arrived and I lost my balance finishing up stumbling downwind just about hanging on to the sheets. Managed to guide them back into the container where they're sitting now with a slight curve in the middle. Straight home again and didn't even think of going up there yesterday or today.